Ultra-aeration air flotation device for wet-process phosphoric acid production and wet-process phosphoric acid production system

Abstract

The utility model provides an ultra-aeration flotation device for wet-process phosphoric acid production and a wet-process phosphoric acid production system, and relates to the technical field of chemical equipment. An ultra-aeration air flotation device is introduced into a wet-process phosphoric acid production process, ultra-aeration micro-bubbles are generated through an aeration generator and output through a plurality of aeration discs in a sleeve structure in an outer shell, and in the floating process of the micro-bubbles, the internal pressure and the external pressure of the ultra-aeration micro-bubbles are gradually unbalanced due to the fact that the pressure of slurry is gradually reduced, so that the micro-bubbles are prevented from floating. The super-aeration micro-bubbles can be broken to generate smaller bubbles, impurities can be adhered to the bubbles, so that the impurities are taken away, finally, the slurry is in a slurry distribution state of an upper air floating layer and a lower floating residue layer, classification can be generated in the classification channel, and the slurry with low impurity content is output at the bottom. And the slurry output from the bottom is filtered to obtain a high-purity phosphoric acid product, so that the subsequent refining cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical equipment, in particular to a super aeration floatation device for wet process phosphoric acid production and a wet process phosphoric acid production system. Background Art

[0002] The existing wet-process phosphoric acid production process is to put phosphate rock, acid and water into the reaction, and carry out liquid-solid reaction in a multi-stage reaction tank in sequence. This process is collectively referred to as extraction reaction in the field of phosphorus chemical industry, which is essentially a liquid-solid reaction process. After the extraction reaction, an extraction slurry is obtained, and then the crystal growing process (crystal growing slurry) and filtering equipment are used to filter the crystal growing slurry to obtain liquid product phosphoric acid and solid waste phosphogypsum. Whether to perform flash cooling is determined according to the temperature of the slurry to be filtered.

[0003] The existing wet-process phosphoric acid production equipment mainly includes extraction tanks, crystal growing tanks and filtering equipment, etc. The produced phosphoric acid still has a high impurity content and requires a large refining cost. In addition, the phosphogypsum produced by the existing wet-process phosphoric acid production equipment is difficult to be directly used as phosphogypsum for construction. The cost of treating solid waste phosphogypsum is far greater than the value of the phosphogypsum for construction itself, and the economic benefits are extremely poor, which seriously restricts the industrial application of phosphogypsum.

[0004] Therefore, there is an urgent need to improve the production equipment of wet phosphoric acid in order to obtain high-quality phosphoric acid and phosphogypsum products and improve the economic benefits of the enterprise.

[0005] In view of this, the present utility model is proposed. Utility Model Content

[0006] The utility model aims to provide a super aeration floatation device and a wet process phosphoric acid production system for wet process phosphoric acid production, aiming to improve the purity of the prepared phosphoric acid product and facilitate the direct utilization of the produced phosphogypsum.

[0007] The utility model is achieved in this way:

[0008] In a first aspect, the utility model provides a super aeration floating device for wet phosphoric acid production, comprising an outer shell, a casing structure is arranged in the outer shell, the casing structure is formed by a plurality of pipelines being arranged in sequence, a connecting hole is arranged between two adjacent pipelines, an aeration structure is arranged between two adjacent pipelines, the aeration structure comprises a connecting pipe and a plurality of aeration disks, the plurality of aeration disks are spaced apart and distributed on the connecting pipe, and the connecting pipe is connected to an external aeration generator;

[0009] A feed port is arranged at the bottom of the super aeration floating device, a grading channel is formed between the outermost pipeline in the casing structure and the outer shell, a first discharge port is arranged on the top side wall of the grading channel, and a second discharge port is arranged at the bottom of the grading channel.

[0010] In an optional embodiment, the sleeve structure is formed by sequentially sleeve-mounting an inner layer pipeline, an intermediate layer pipeline and an outermost layer pipeline, and a plurality of first communication holes are distributed on the wall of the inner layer pipeline; a plurality of second communication holes are distributed on the wall of the intermediate layer pipeline;

[0011] A primary aeration structure is arranged in the inner pipeline, a secondary aeration structure is arranged between the inner pipeline and the middle pipeline, and a tertiary aeration structure is arranged between the middle pipeline and the outermost pipeline. The installation heights of the primary aeration structure, the secondary aeration structure and the tertiary aeration structure gradually increase.

[0012] In an optional embodiment, the first connecting holes are distributed from the top to the bottom of the inner pipeline, and the second connecting holes are distributed in the area of ​​the middle pipeline above the secondary aeration structure.

[0013] In an optional embodiment, a bottom plate is further included, which is arranged at the bottom of the sleeve structure, and a feed port is arranged on the bottom plate, and the position of the feed port corresponds to the inner pipeline.

[0014] In an optional embodiment, a third discharge port is provided on the bottom plate between the inner pipeline and the middle pipeline, and a fourth discharge port is provided on the bottom plate between the middle pipeline and the outermost pipeline.

[0015] In an optional embodiment, the height of the outermost pipeline is higher than that of the inner pipeline and the middle pipeline.

[0016] In an optional embodiment, a first dynamic settler is provided on the top of the outermost pipeline.

[0017] In an optional embodiment, the top of the outermost pipeline is spaced apart from the top of the outer shell to form an overflow port for overflowing from the outermost pipeline to the grading channel.

[0018] In an optional embodiment, a second dynamic settler is provided on the grading channel, and the first discharge port is located above the second dynamic settler.

[0019] In a second aspect, the utility model provides a wet-process phosphoric acid production system, comprising the super-aeration flotation device of any one of the aforementioned embodiments.

[0020] The utility model has the following beneficial effects: by introducing a super-aeration flotation device into the wet phosphoric acid production process, super-aeration micro-bubbles are generated through an aeration generator, and the super-aeration micro-bubbles are output through a plurality of aeration disks in a sleeve structure in an outer shell body. In the process of micro-bubbles floating up, the slurry pressure gradually decreases, so that the internal and external pressures of the super-aeration micro-bubbles gradually become unbalanced, and the super-aeration micro-bubbles will rupture to produce smaller bubbles, which can make impurities adhere to the bubbles, thereby taking away the impurities, and finally making the slurry present a slurry distribution state of an upper air flotation layer and a lower floating residual layer, and grading can be generated in a grading channel, and slurry with a lower impurity content is output at the bottom, and the slurry output at the bottom is filtered to obtain a high-purity phosphoric acid product, thereby reducing the subsequent refining cost.

[0021] In addition, the phosphogypsum components obtained after filtering the slurry output from the top and bottom of the grading channel are different. The phosphogypsum products with higher purity can be obtained after filtering the slurry output from the bottom, which is conducive to direct use as phosphogypsum for construction; the phosphogypsum with higher impurity content can be obtained after filtering the slurry output from the top, but impurities such as organic matter, fluoride, and residual phosphorus are beneficial to crops and can be output as agricultural phosphogypsum products. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of a super aeration floating device provided in an embodiment of the utility model;

[0024] Figure 2 for Figure 1 Schematic diagram of the aeration structure;

[0025] Figure 3 for Figure 1 Dimensional illustration of the Zhongchao aeration floatation device;

[0026] Figure 4 A schematic structural diagram of an overexposure generator provided in an embodiment of the utility model.

[0027] Icons: 100-super aeration floating device; 001-feeding port; 002-grading channel; 003-first discharge port; 004-second discharge port; 005-third discharge port; 006-fourth discharge port; 007-overflow port; 110-outer shell; 121-outermost pipeline; 122-middle pipeline; 1221-second connecting hole; 123-inner pipeline; 1231-first connecting hole; 130-aeration structure; 131-connecting pipe; 132-aeration plate; 133-aeration generator; 134-first aeration structure; 135-secondary aeration structure; 136-third aeration structure; 140-bottom plate; 151-first dynamic settler; 152-second dynamic settler;

[0028] 400-overexposure generator; 410-generating container; 420-liquid delivery pipeline; 421-fifth valve; 430-compressed gas delivery pipeline; 431-top delivery pipeline; 432-bottom delivery pipeline; 433-first valve; 434-second valve; 435-third valve; 440-gas-liquid mixture output pipeline; 441-fourth valve; 450-safety valve; 460-pressure detection mechanism. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0033] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0034] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] The embodiment of the utility model provides a super-aeration flotation device 100 for wet-process phosphoric acid production, which is used to treat the extraction slurry obtained in the traditional wet-process phosphoric acid production process. By introducing super-aeration microbubbles, the slurry classification is promoted and the impurities are concentrated in the upper layer of the slurry, so that the extraction slurry can be divided into an upper flotation layer and a lower floating residue layer.

[0036] Please refer to Figure 1 The super aeration flotation device 100 includes an outer shell 110, in which a casing structure is arranged. The casing structure is formed by a plurality of pipelines being arranged in sequence, and a connecting hole is arranged between two adjacent pipelines so that the material in the inner pipeline can enter the outer pipeline. An aeration structure 130 is arranged between two adjacent pipelines, and the aeration structure 130 is obtained according to the number of pipelines in the casing structure, and the specific number is not limited.

[0037] Furthermore, a feed port 001 is provided at the bottom of the super aeration flotation device 100, a grading channel 002 is formed between the outermost layer pipeline 121 in the casing structure and the outer shell 110, a first discharge port 003 is provided on the top side wall of the grading channel 002, and a second discharge port 004 is provided at the bottom of the grading channel 002. The extraction slurry enters the casing structure from the feed port 001, undergoes aeration treatment through multiple aeration structures 130, causes impurities to float up with bubbles, and is finally graded in the grading channel 002, and slurry with relatively high impurity content is output at the first discharge port 003 at the top, and slurry with low impurity content is output at the second discharge port 004 at the bottom.

[0038] It should be added that the slurry output from the bottom of the grading channel 002 can be filtered to obtain high-purity phosphoric acid products and phosphogypsum products. The phosphogypsum product has very little impurity content, which is conducive to direct use as building phosphogypsum (i.e. industrial phosphogypsum); the slurry output from the top can be filtered to obtain phosphogypsum with a higher impurity content, but impurities such as organic matter, fluoride, and residual phosphorus are beneficial to crops and can be output as agricultural phosphogypsum products.

[0039] In some embodiments, the casing structure may be a three-stage casing structure, with a three-stage aeration structure. The casing structure is formed by sequentially setting the inner layer pipeline 123, the middle pipeline 122 and the outermost pipeline 121, and a plurality of first connecting holes 1231 are distributed on the wall of the inner layer pipeline 123, and a plurality of second connecting holes 1221 are distributed on the wall of the middle pipeline 122. After the extraction slurry enters from the inner layer pipeline 123, it enters the middle pipeline 122 from the first connecting hole 1231, and then enters the outermost pipeline 121 from the second connecting hole 1221. The tops of the inner layer pipeline 123, the middle pipeline 122 and the outermost pipeline 121 may be closed or open.

[0040] Further, a primary aeration structure 134 is provided in the inner layer pipeline 123, a secondary aeration structure 135 is provided between the inner layer pipeline 123 and the middle pipeline 122, and a tertiary aeration structure 136 is provided between the middle pipeline 122 and the outermost layer pipeline 121, and the installation heights of the primary aeration structure 134, the secondary aeration structure 135, and the tertiary aeration structure 136 gradually increase. The primary aeration structure 134, the secondary aeration structure 135, and the tertiary aeration structure 136 are all connected to the external aeration generator 133, that is, a tertiary aeration generator is installed on the outer shell 110, the primary aeration structure 134 corresponds to the primary aeration generator, the secondary aeration structure 135 corresponds to the secondary aeration generator, and the tertiary aeration structure 136 corresponds to the tertiary aeration generator.

[0041] Specifically, please combine Figure 1 and Figure 2The aeration structure 130 includes a connecting pipe 131 and a plurality of aeration plates 132. The plurality of aeration plates 132 are spaced apart on the connecting pipe 131. The connecting pipe 131 is connected to an external aeration generator 133. The structure of the aeration plate 132 is similar to a shower head, and the gas-liquid mixture is sprayed out through a plurality of water outlets. The aeration generator 133 can pressurize the liquid and introduce gas into the pressurized liquid to form a gas-liquid mixed phase. For example, a container may be included, and a liquid infusion pipeline and a gas supply pipeline are arranged on the container. The liquid is first introduced into the container, and gas is introduced to the top of the container through the gas supply pipeline for pressurization. Then, gas is introduced to the bottom of the container through the gas supply pipeline to form a gas-liquid mixed phase; finally, gas is introduced into the top of the container and the outlet valve is opened to output the gas-liquid mixed phase.

[0042] It should be noted that the super-aerated microbubbles are generated by the aeration generator, and the super-aerated microbubbles form a gas-liquid mixed phase in a pressurized liquid phase, the pressure of the liquid phase is 0.1MPa-1.0MPa, the gas phase includes microbubbles with a diameter of 0.1μm-50μm, the proportion of the gas phase to the gas-liquid mixed phase is 1wt%-30wt%, and the mass ratio of the gas-liquid mixed phase to the extraction slurry is (5-30): 100. By optimizing the specific operating parameters of the super-aerated microbubbles, the effect of impurity removal can be improved, the purity of the phosphoric acid product can be further improved, and the refining cost can be reduced.

[0043] In some embodiments, the liquid phase is at least one of system slurry, wash water and return acid. System slurry refers to the extraction slurry in the wet phosphoric acid system; wash water refers to the wash water obtained by washing the solid after filtering the floating layer; and return acid refers to the dilute phosphoric acid obtained after filtering the floating layer and the floating layer.

[0044] In some embodiments, a bubble surface modifier can be added to the liquid phase, and the dosage of the bubble surface modifier is 1.0 mg / L-4.0 mg / L. By adding a bubble surface modifier, the adhesion effect of impurities can be enhanced, thereby taking away impurities, and finally the slurry will be in the slurry distribution state of the upper air flotation layer and the lower floating layer, and the slurry of the upper air flotation layer and the lower floating layer will be separated and filtered separately. The inventor found that the filtrate obtained by filtering the air flotation layer and the floating layer is a phosphoric acid product of good quality, and the filter cake obtained by filtering the floating layer meets the relevant standards of building materials, so that the properties of phosphogypsum building materials are greatly improved. The filter cake obtained by filtering the air flotation layer meets the relevant standards of agricultural materials after blocking the mobility of heavy metals to the soil by chemical curing. The bubble surface modifier is selected from at least one of hexadecyltrimethylammonium bromide, polydimethyldiallyl ammonium chloride and quaternary ammonium salt chitosan, and can be any one or more of the above. The above bubble surface modifiers can further enhance the removal effect of impurities, and the raw materials are easy to obtain.

[0045] Further, the first connecting holes 1231 are distributed from the top to the bottom of the inner pipeline 123, that is, the first connecting holes 1231 are a porous structure as a whole. The second connecting holes 1221 are distributed in the area of ​​the middle pipeline 122 above the secondary aeration structure 135, so that the slurry after aeration treatment enters the outermost pipeline 121 from the top. The outermost pipeline 121 may not be provided with a connecting hole, and the top of the outermost pipeline 121 and the top of the outer shell 110 are arranged at intervals to form an overflow port 007 from the outermost pipeline 121 to the grading channel 002, so that the slurry enters the grading channel 002 from the overflow port 007. Specifically, the opening rate of the inner pipeline 123 can be about 36%, and the opening rate on the middle pipeline 122 can be about 30%.

[0046] In some embodiments, the super aerated floating device 100 further includes a bottom plate 140 , which is disposed at the bottom of the casing structure. A feed port 001 is disposed on the bottom plate 140 , and a position of the feed port 001 corresponds to the inner layer pipeline 123 , and feed can be fed from the center of the inner layer pipeline 123 .

[0047] Furthermore, a third discharge port 005 is provided on the bottom plate 140 between the inner layer pipeline 123 and the middle layer pipeline 122, and a fourth discharge port 006 is provided on the bottom plate 140 between the middle layer pipeline 122 and the outermost layer pipeline 121. The slurry outputted from the third discharge port 005 and the fourth discharge port 006 is slurry with relatively low impurity content, and can be outputted as industrial-grade phosphogypsum.

[0048] In some embodiments, the height of the outermost pipeline 121 is higher than that of the inner pipeline 123 and the middle pipeline 122. A first dynamic settler 151 is provided on the top of the outermost pipeline 121. The first dynamic settler 151 is used to enhance the grading effect and concentrate more impurities in the upper layer of the slurry.

[0049] Similarly, a second dynamic settler 152 is provided on the grading channel 002, and the first discharge port 003 is located above the second dynamic settler 152. A dynamic settler is also provided on the grading channel 002 to further improve the grading effect and concentrate more impurities in the upper slurry.

[0050] Specifically, the first dynamic settler 151 and the second dynamic settler 152 are both existing dynamic settlers, such as dynamic settlers used to solve sludge sedimentation in sewage treatment. As shown in the figure, the first dynamic settler 151 can be installed with the help of a plate-like structure with multiple holes on the top and bottom, and the second dynamic settler 152 can also be installed with the help of a plate-like structure with multiple holes on the top and bottom, and the opening rate can be 30%.

[0051] Specifically, the sizes of the various parts of the super aeration flotation device 100 are not limited and can be designed according to the process requirements. The diameter of the outer shell 110 can be 900-1100mm, such as 1000mm; the diameter of the outermost pipeline 121 can be 600-800mm, such as 700mm; the diameter of the middle pipeline 122 can be 400-600mm, such as 500mm; the diameter of the inner pipeline can be 100-200mm, such as 150mm. The diameter of the feed port 001 can be 80mm, and the diameter of the discharge port can be 100mm.

[0052] like Figure 3 As shown, the heights of the various parts are a: 303mm; b: 180mm; c: 120mm; d: 230mm; e: 250mm; f: 230mm; g: 230mm; and h: 330mm. The dimensions of the first dynamic settler 151 and the second dynamic settler 152 are as shown in FIG. Figure 3 As shown, the unit is mm.

[0053] Specifically, the material of the super aeration floating device 100 needs to be resistant to corrosion by 30% phosphoric acid and 40% sulfuric acid, and has the characteristics of high temperature resistance and high pressure resistance, and is suitable for working under the conditions of 100°C and 0.1MPa. It is recommended that the material can be PC material, and PC pipes should be selected as much as possible.

[0054] In some embodiments, the aeration generator can be constructed as follows: Figure 4 As shown, Figure 4 The working principle of the super exposure generator 400 is as follows: (1) open the fifth valve 421, use the liquid delivery pipeline 420 to input liquid or slurry into the generating container 410, and close the fifth valve 421; (2) open the third valve 435 and the first valve 433 to pressurize the liquid in the generating container 410 through the compressed gas delivery pipeline 430 and the top delivery pipeline 431, and after meeting the process requirements, close the first valve 433; (3) open the third valve 435 and the second valve 434, and pressurize the liquid in the generating container 410 through the compressed gas delivery pipeline 430 and the top delivery pipeline 431. The bottom delivery pipeline 432 performs pressurized aeration in the pressurized liquid in the generating container 410 to form a pressurized gas-liquid mixture. After the process requirements are met, the third valve 435 and the second valve 434 are closed; (4) The third valve 435, the first valve 433 and the fourth valve 441 are opened, and compressed gas is input to the top of the generating container 410 through the compressed gas delivery pipeline 430 and the top delivery pipeline 431 to pressurize the pressurized gas-liquid mixture, so that the pressurized gas-liquid mixture is output from the gas-liquid mixture output pipeline 440, and the over-exposure liquid is sent to the target area. The pressure detection mechanism 460 is used for pressure detection during the whole process, and the safety valve 450 alarms when it exceeds the specified range.

[0055] It should be noted that "superexposure" refers to the formation of a pressurized gas-liquid mixture, which differs from conventional bubbling mainly in the pressurization.

[0056] The embodiment of the utility model further provides a wet-process phosphoric acid production system, which includes the above-mentioned super-aeration floatation device 100, and may also include an extraction tank, a crystal growing tank, and a flash tank, etc.

[0057] Specifically, phosphate rock and inorganic acid are mixed for extraction, and then crystal growth is performed. The extraction and crystal growth can be performed in two tanks respectively, and the slurry after extraction can overflow into the crystal growth tank for crystal growth. A flash tank can be added for cooling according to process requirements. The slurry obtained after the extraction, crystal growth and other processes is the extraction slurry, and the extraction slurry is treated by the super aeration flotation device 100.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A super aeration flotation device for wet process phosphoric acid production, characterized in that: It comprises an outer shell, in which a sleeve structure is arranged, the sleeve structure is formed by a plurality of pipelines being sleeved in sequence, a connecting hole is arranged between two adjacent pipelines, an aeration structure is arranged between two adjacent pipelines, the aeration structure comprises a connecting pipe and a plurality of aeration plates, the plurality of aeration plates are spaced apart and distributed on the connecting pipe, and the connecting pipe is connected to an external aeration generator; A feed port is provided at the bottom of the super aeration floating device, a grading channel is formed between the outermost pipeline in the casing structure and the outer shell, a first discharge port is provided on the top side wall of the grading channel, and a second discharge port is provided at the bottom of the grading channel.

2. The super aeration floating device according to claim 1, characterized in that: The sleeve structure is formed by sequentially sleeve-mounting an inner layer pipeline, an intermediate layer pipeline and an outermost layer pipeline, wherein a plurality of first communication holes are distributed on the pipe wall of the inner layer pipeline; a plurality of second communication holes are distributed on the pipe wall of the intermediate layer pipeline; A primary aeration structure is arranged in the inner pipeline, a secondary aeration structure is arranged between the inner pipeline and the middle pipeline, and a tertiary aeration structure is arranged between the middle pipeline and the outermost pipeline. The installation heights of the primary aeration structure, the secondary aeration structure and the tertiary aeration structure gradually increase.

3. The super aeration floating device according to claim 2, characterized in that: The first connecting holes are distributed from the top to the bottom of the inner pipeline, and the second connecting holes are distributed in the area of ​​the middle pipeline above the secondary aeration structure.

4. The super aeration floating device according to claim 2, characterized in that: It also includes a bottom plate, which is arranged at the bottom of the sleeve structure. The feed port is arranged on the bottom plate, and the position of the feed port corresponds to the inner layer pipeline.

5. The super aeration floating device according to claim 4, characterized in that: A third discharge port is provided on the bottom plate between the inner layer pipeline and the middle layer pipeline, and a fourth discharge port is provided on the bottom plate between the middle layer pipeline and the outermost layer pipeline.

6. The super aeration floating device according to claim 2, characterized in that: The height of the outermost pipeline is higher than that of the inner pipeline and the middle pipeline.

7. The super aeration floating device according to claim 6, characterized in that: A first dynamic settler is arranged on the top of the outermost pipeline.

8. The super aeration floating device according to claim 6, characterized in that: The top of the outermost pipeline is spaced apart from the top of the outer shell to form an overflow port for overflowing from the outermost pipeline to the grading channel.

9. The super aeration floating device according to claim 8, characterized in that: A second dynamic settler is arranged on the grading channel, and the first discharge port is located above the second dynamic settler.

10. A wet process phosphoric acid production system, characterized in that: The super aeration floating device comprises the super aeration floating device according to any one of claims 1 to 9.

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